package mo.offer_special;

public class L104 {

    public int combinationSum4(int[] nums, int target) {
        int[] dp = new int[target+1];
        dp[0] = 1;
        for (int i = 1; i <= target; i++) {
            for (int num : nums) {
                if (i >= num) {
                    dp[i] += dp[i-num];
                }
            }
        }
        return dp[target];
    }

    public static void main(String[] args) {
        L104 test = new L104();
        System.out.println(test.combinationSum4(new int[]{1, 2, 3}, 4));
    }

}
